Elinor Barker has already staked her claim for the fourth place in Great Britain's women's pursuit team. Photograph: Bryn Lennon/Getty Images

From next year the women's team pursuit will add another rider and a further 1,000 metres in the switch to four women over 4,000m but on Thursday night's showing here at the World Track Championships it is unlikely to cause Great Britain even to draw breath. As Laura Trott said after taking gold, it is "just another kilometre". The British women have every right to be confident for the future after continuing to dominate the discipline while the fourth rider has already staked her claim.

The Olympic champion Joanna Rowsell, a mainstay of the team since 2008, is currently on sabbatical but the Welsh schoolgirl Elinor Barker looks every bit the part on her showing here alongside the London gold medallists Trott and Dani King, as Great Britain's women won their fifth world title in the discipline in six years to go with the Olympic title and world record from last year in London.

As for Barker, the 18-year-old from Cardiff is still doing her A-levels in biology and PE, although she has managed only a couple of days in school this year due to her training and the poor weather, and was riding the junior world road race championships less than six months ago – she won gold in the time trial to follow up her silver medal of 2011 – but one would barely have known it.

The trio qualified fastest and followed that with a near two-second beating of Australia in the final, in spite of their opponents benefiting from a pair of fresh legs having drafted in Amy Cure to replace Ashlee Ankudinoff. They were seamless rides, with Barker showing ability beyond her years. A cyclist since the age of 10, when she began racing with the Maindy Flyers in Cardiff in order to get out of swimming lessons, Barker will join the GB academy full time when her studies are over.

"She has a good work ethic and, given that she is still in school, obviously she's very organised and she has plenty of ability to go with it," was the summary of her coach Paul Manning. "She's benefited from the input of the Great Britain junior programme and the Welsh programme in Newport with [Welsh head coach] Darren Tudor. They've done well fitting in sessions alongside her school and so on over the winter."

Afterwards Barker had the look of a young woman who could not believe what had hit her. "Overwhelmed," she said, adding that she had attempted to calm herself by imagining she was at a training session in Manchester, and the magnitude of her first senior world title had dawned on her only at the very end.

The dominant individual on Thursday was Ireland's Martyn Irvine, who gave his country its best day at any cycling world championships with a silver in the pursuit followed with a gold in the scratch race – a tribute to his drive and determination given that his country has little funding and no indoor velodrome – as well as an extra fillip on the day it was confirmed that Belfast will host the Giro d'Italia start in 2014.